[ColinDabritz]

On a brief look, it appears that all of these choices (Including Amazon's new one) only support Android devices and not iOS?

I believe Xamarin Test Cloud includes iOS, although I'm not certain if it integrates outside of the Xamarin framework. http://xamarin.com/test-cloud

Seems like a gap they should all be trying to fill.

[rasmuskl]

Xamarin Test Cloud is not limited to Xamarin apps for either platform.

Disclaimer: I work at Xamarin.

[babababa]

Apple developer program licensing agreements make it very hard to (legally) provide iOS devices for remote testing.